My weight painting only works at 100% no matter the shade
This is how weights work.

The weight doesn't define an influence of a particular bone; It describes the Mix factor of influence between multiple bones.

So a vertex with 1% weight on one bone and 0% on all other bones will be 100% influenced by the 1% bone.
A vertex with 1% weight on one bone and 50% weight on another bone will be almost entirely controlled by the 50% bone.

In other words, a vertex is always influenced 100%. Weight only controls which bones do the influencing.



To get a result similar to what I think you are expecting, add a second bone weighted to all the vertices by 100%. Now the first bone's weights will cause non-uniform influences, as you might expect.